A type of system that uses circulating pumps and fans to collect and distribute heat.

Alternative Energy

Any source of energy other than fossil fuels that is used for constructive purposes.

Ampere

The unit of electric current in the meter-kilogram-second system of units. Referred to as amp and symbolized as A.

Conduction

The transfer of heat within an object or between objects by molecular activity, without any net external motion.

Convection

Process by which, in a fluid being heated, the warmer part of the mass will rise and the cooler portions will sink.

Current

The net transfer of electric charge (electron movement along a path) per unit of time.

Electrical Energy

Energy caused by the movement of electrons.

Electricity

The flow of electrical power or charge.

Electromagnetic Energy

Energy caused by the movement of light waves.

Electrolysis

The process separating the hydrogen-oxygen bond in water using an electrical current.

Energy

The ability to do work.

Entropy

The function of the state of a thermodynamic system whose change in any differential reversible process is equal to the heat absorbed by the system from its surroundings divided by the absolute temperature of the system.

First Law of Thermodynamics

The law that heat is a form of energy, and the total amount of energy of all kinds in an isolated system is constant; it is an application of the principle of conservation of energy. Also known as conservation of energy.

Fuel Cell Stack

Individual fuel cells that are combined in series.

Heat

Energy in transit due to a temperature difference between the source from which the energy is coming and a sink toward which the energy is going.

Kelvin

A unit of absolute temperature and symbolized as K. Formerly known as degree Kelvin.

Line of Best Fit

A straight line that best represents all data points of a scatter plot. This line may pass through some, all, or none of the points displayed by the scatter plot. Also referred to as a Trend Line or Regression Line.

Ohm

The unit of electric current in the meter-kilogram-second system of units. Symbolized as Ω.

Ohm’s Law

States that the direct current flowing in an electric circuit is directly proportional to the voltage applied to the circuit.

Passive Solar Energy Collection

Systems that do not make use of any externally powered, moving parts, such as circulation pumps, to move heated water or air.

Product Development Lifecycle

Stages a product goes through from concept and use to eventual withdrawal from the market place.

Radiation

The process by which energy is transmitted through a medium, including empty space, as electromagnetic waves. This energy travels at the speed of light. This is also referred to as electromagnetic radiation.

Renewable Energy

A resource that can be replaced when needed.

Resistance

The opposition that a device or material offers to the flow of direct current.

R-value

The measure of resistance to heat flow.

Second Law of Thermodynamics

A general statement of the idea that there is a preferred direction for any process.

Temperature

A property of an object which determines the direction of heat flow when the object is placed in thermal contact with another object.

Thermal Equilibrium

Refers to the property of a thermodynamic system in which all parts of the system have attained a uniform temperature which is the same as that of the system’s surroundings.

Thermodynamic System

A part of the physical world as described by its thermodynamic properties such as temperature, volume, pressure, concentration, surface tension, and viscosity.

Thermodynamics

The study of the effects of work, heat, and energy on a system.

U-value

A measure of thermal transmittance through a material.

Volt

The unit of potential difference symbolized as V.

Voltage

The potential difference measured in volts. The amount of work to be done to move a charge from one point to another along an electric circuit.

Zeroth Law of Thermodynamics

A law that if two systems are separately found to be in thermal equilibrium with a third system, the first two systems are in thermal equilibrium with each other; that is, all three systems are at the same temperature.